Field of the Invention
The present invention relates to an image stabilization control apparatus for reducing image blur in optical apparatuses such as digital cameras and interchangeable lenses.
Description of the Related Art
Image stabilization techniques for correcting (reducing) image blur due to a camera shake caused by user's hand jiggling or the like when a digital camera performs still image capturing include optical image stabilization that shifts a lens or an image sensor (such as a CMOS sensor) relative to an image capturing optical axis. The camera shake is detected by using a shake detector such as an angular velocity sensor (gyro sensor) or by calculating a motion vector between frame images included in a captured motion image as disclosed in Japanese Patent Laid-Open No. 05-122590.
However, using the shake detector may cause superposition of a low-frequency noise (error component) called a drift component on a sensor output corresponding to the original camera shake and thereby decrease camera shake detection accuracy, which results in an insufficient image stabilization control. On the other hand, using the motion vector enables accurately detecting the camera shake. However, the motion vector is not detectable during an exposure time period of the image sensor for capturing a still image, so that the image stabilization control using the motion vector cannot be performed during that exposure time period.